Pesticide Use on Fruit and Vegetable Crops in Ohio 1990

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The significance of organic carbon and nutrient export from peatland-dominated landscapes subject to disturbance, a stoichiometric perspective

The terrestrial-aquatic interface is a crucial environment in which to consider the fate of exported terrestrial carbon in the aquatic system. Here the fate of dissolved organic carbon (DOC) may be controlled by nutrient availability. However, peat-dominated headwater catchments are normally of low nutrient status and thus there is little data on how DOC and nutrient export co-varies. We present nutrient and DOC data for two UK catchments dominated by peat headwaters. One, Whitelee, is undergoing development for Europe's largest windfarm. Glen Dye by comparison is relatively undisturbed. At both sites there are significant linear relationships between DOC and soluble reactive phosphorus and nitrate concentrations in the drainage waters. However, inter-catchment differences exist. Changes in the pattern of nutrient and carbon export at Whitelee reveal that landscape disturbance associated with windfarm development impacts the receiving waters, and that nutrient export does not increase in a stoichiometric manner that will promote increase in microbial biomass but rather supports aquatic respiration. In turn greater CO2 efflux may prevail. Hence disturbance of terrestrial carbon stores may impact the both the aquatic and gaseous carbon cycle. We suggest estimates of aquatic carbon export should inform the decision-making process prior to development in ecosystems and catchments with high terrestrial carbon storage

Determining trophic niche width: a novel approach using stable isotope analysis

1. Although conceptually robust, it has proven difficult to find practical measures of niche width that are simple to obtain, yet provide an adequate descriptor of the ecological position of the population examined. 2. Trophic niche has proven more tractable than other niche dimensions. However, indices used as a proxy for trophic niche width often suffer from the following difficulties. Such indices rarely lie along a single scale making comparisons between populations or species difficult; have difficulty in combining dietary prey diversity and evenness in an ecologically meaningful way; and fail to integrate diet over ecological time-scales thus usually only comprise single snapshots of niche width. 3. We propose an alternative novel method for the comparison of trophic niche width: the use of variance of tissue stable isotope ratios, especially those of nitrogen and carbon. 4. This approach is a potentially powerful method of measuring trophic niche width, particularly if combined with conventional approaches, because: it provides a single measure on a continuous axis that is common to all species; it integrates information on only assimilated prey over time; the integration period changes with choice of tissue sampled; and data production is theoretically fast and testing among populations simple. 5. Empirical studies are now required to test the benefits of using isotopic variance as a measure of niche width, and in doing so help refine this approach

Policies, Practices, Places, and People: How Elementary Preservice Teachers Learned Literacy Teaching

This article features cases of how elementary education preservice teachers made sense of teaching literacy. Their contexts for teaching varied in policies, curricula, and demands for their literacy teaching, shaped their learning and understanding of literacy instruction and assessment as beginning teachers. The research featured in this article pushes upon conceptualizations of good literacy teaching and how mentor teachers serve a critical role in preparing the next generation of elementary literacy teachers. Recommendations are made on how to best support elementary preservice teachers in literacy instruction and assessment

What is a certified public accountant

It seems strange to those of us who are daily performing our work as Certified Public Accountants, that the whole world should not know what we profess to be. It is true, however, that to many-otherwise intelligent and well-informed persons, the Certified Public Accountant is unknown. I have failed to find, however, in any instance, that the preparation of the Certified Public Accountant, from his very beginning to a point where his professional brethren universally would admit his claim to equal consideration before the public, has been ever so considered, and explained, that an outsider might readily understand it. To write that one must meet the legal requirements for an examination, is one thing; and to describe what these requirements are is another thing, and better suited for our purpose